|Joanna "Jo" Portman|
|First seen||The Book|
|Last seen||Series 8, Episode 3|
|Job||Section D, Junior Case Officer|
Jo Portman was an aspiring journalist trying to make contact with high profile journalist Gary Hicks. After coming to the attention of Section D, she came in to contact with Adam when he posed as a gasman to check her out.
After spotting Adam with Hicks later on, she became suspicious and followed Adam, Zaf and Hicks to an MI5 safe house. A later encounter with Adam, who gave a fake story about being part of a private security firm, didn't get rid of her suspicions and led to her staking out the safe house. This proved fortuitous as she tipped off Zaf and Ruth to the presence of a government hit squad coming after Hicks.
After smashing the assassins' car window and leaving her phone inside, she alerted Section D, who tracked her phone to a dead end. At the conclusion of the episode Adam asked Jo to fill the last spot on the field team, an offer she gratefully accepted.
Jo had many important roles in her time at MI5, like acting as an undercover bodyguard for the Prime Minister's son. She also infiltrates a highly- dangerous group called the Redbacks, accompanied by Adam Carter. Due to fear that she will not be able to withstand torture, she constantly begs Adam to kill her, to put her out of her misery. Special forces storm the building, and Adam is found holding Jo's lifeless body (though it is revealed she was playing dead). As well as this, Adam's death shook Jo badly. She began to see her captor's face in numerous different places, which led to missions being compromised. However, it is later revealed, to Ros, that she was raped multiple times by the Redbacks.
Jo slowly began to rebuild herself, until she was hit again by the death of former-lover Ben Kaplan, who was murdered by Connie James. Once again, she came through this strong. Jo begins to start working to her full, stable capacity once again.
Both Jo and Ros are caught up in a hostage situation, without communications. Jo is tasked with negotiating with the hostage takers, which initially proves successful. However, one terrorist threatens to detonate explosives. After a short struggle, Jo finds herself holding the terrorist from behind. Ros aims, but is reluctant, as she knows Jo could be hit and killed. Jo gives Ros a nod, Ros takes the shot and the bullet hits both the terrorist and Jo. Both die.